Cables carrying multiple conductors especially telecommunications cables which carry a plurality of fine insulated wires within the body of the cable are subject to premature failure when the cable must be cut open to splice the cable either for drop wires or in replacing a section of damaged cable. Once the outer protective jacket of the cable including metal jacket is severed for a splice, the finer inner wires require protection from the ingress of water, and the deliterious action of oxygen, as well as ultraviolet radiation degradation.
Aerial metal canister enclosures seal the cable but require the use of tools such as wrenches and pliers. The manipulation of the tools while in the air is cumbersome and dangerous. Toolless mastic sealing systems are adequate unless the cable splice must be re-entered. The removal of the mastic from the splice area is a time consuming and dirty job. Heat-shrinkable enclosures work well but it is often inappropriate or unsafe to use a torched closure system. Thus it would be desirable to have a toolless environmental seal that avoided the use of mastics or similar adhesives in the splice area.
Splice enclosures such as Trac.TM. Splice Enclosure from Raychem or similar closures provide protection to the fine inner wires from ultraviolet radiation. These closures are preferred by telephone craftspeople because the aerial installation is done without tools. However, a more complete nonsplice area mastic system would be desirable. The environmental seal must minimize the exposure of the inner insulated wires to water or water vapor and oxygen because oxygen attacks the inner plastic insulation which accelerates embrittlement and water exposure causes shorting and crosstalk once the insulation cracks.
Thus, it would be highly desirable to have an environmental closure capable of fitting within a standard aerial enclosure that will enhance the protection of the spliced portion of the cable. However, if the spliced portion of the cable needs to be reentered to introduce additional splices or drop wires, it would be desirable to have a system that provides inconvenient but easy access to the splice, i.e., all other parts of the system are more easily checked but the splice area can be re-entered if the problem is isolated to the splice area.
It is thus an object of this invention to provide an environmental control liner capable of fitting within an existing aerial enclosure and sealing the splice region while providing inconvenient but easy access to the splice area once the craftsperson decides reentry to the splice is necessary. It is also an object of this invention to provide enhanced moisture, vapor and oxygen protection for the fine wires within the cable. A still further object of the invention is to avoid the need to remove any installed sealing mastic adhesive to enter the splice. Additional objects of the invention will be apparent from the following description.